Senior C++ Developer
First seen by Alion on Jun 16, 2026.
Become part of a rapidly growing technology company with an important purpose of developing the best software products to prevent and fight crime. We make sure that police authorities and intelligence services always have the best technological solutions, giving them optimal conditions to protect citizens in the city, on the street and in our homes.
If you are motivated by working in a dynamic, innovative environment where you actively contribute to creating impactful technological solutions, and have deep experience with high-performance C++ and real-time data processing at scale, you might be the skilled Senior Software Developer we need on our team. You will take part in knowledge-sharing and cross-functional collaboration, all while being driven by meaningful impact through technical excellence.
Build high-performance systems that process data at scale
Your primary role will be to design, develop and maintain real-time, scalable and testable, high-quality software systems where performance is critical. You'll work on technical challenges that demand deep expertise in performance optimization, concurrent programming, and distributed system design.
The technical challenges you'll solve:
Processing and analyzing real-time data streams at scale with strict latency requirements
Optimizing system performance through profiling, bottleneck analysis, and architectural improvements
Designing and implementing highly concurrent C++ services that efficiently utilize modern multi-core processors
Building scalable architectures that handle massive data volumes while maintaining reliability and maintainability
You will translate ideas into new features, as well as improving existing software. Beyond writing code, you'll have significant influence over architectural decisions, mentor junior developers, and help mature our engineering practices. You will join a dedicated and experienced team where professionalism is high, the atmosphere is informal, and colleagues support and challenge each other.
Areas of responsibility
Design and implement high-performance C++ services that handle real-time data at scale
Optimize system performance through profiling, benchmarking, and architectural refinement
Architect solutions for concurrent and parallel data processing on modern hardware
Lead code reviews and establish best practices for clean, maintainable, high-performance code
Mature our CI/CD workflows, testing strategies (unit, integration, and performance testing), and monitoring tools
Mentor and train junior developers, sharing your expertise in software architecture and system design
Collaborate across teams to integrate diverse technologies and competencies
About you
You have 5+ years of experience with software development and have a proven track record of building high-performance, scalable systems. You excel at writing clean, structured code that runs fast, and you know how to systematically identify and eliminate performance bottlenecks.
You understand the intricacies of concurrent programming and have experience designing systems that efficiently leverage multi-core architectures. You're comfortable making architectural decisions and can balance trade-offs between performance, maintainability, and scalability.
You are motivated by continuous learning and have a natural interest in exploring new technologies within the field. You find it exciting to contribute to the improvement of public safety through innovative tech solutions.
Furthermore, you are a strong team player who shares valuable ideas and knowledge with your colleagues. You communicate effectively in English, both in writing and speaking.
You have experience with
We imagine you have some experience with the following:
Design and implementation of highly performant and scalable software systems
Advanced C++ programming (modern C++17 or later)
Performance optimization, profiling tools, and benchmarking methodologies
Concurrent and parallel programming, multithreading, and synchronization
Network technologies and/or telecommunications
Software architecture patterns and SOLID principles
Modern development practices including CI/CD, automated testing, and code review
It's a further advantage if you have worked with:
Apache Kafka or other distributed streaming platforms
Intel DPDK or other high-performance networking frameworks
Docker and/or Kubernetes
Linux systems programming
Distributed systems design
If you don’t tick all the boxes above, please do apply anyway. We strongly believe in personal and professional development as part of the job, so if you have a positive attitude and natural curiosity, you’ll have plenty of opportunity for learning and growth.
Be part of the XCI-Team
You will be part of our creative community of 170+ experts who believe in XCI's core purpose of protecting us all from criminal threats. Our projects present complex technical challenges that have real meaning and contribute to making society safer.
As part of the XCI team, you should expect to work with motivated and happy colleagues in a dynamic work environment. The informal XCI culture has "freedom under responsibility" as its internal motto, which allows you flexible working hours and a good work/life balance. We prioritize employee development very highly and there is always a focus on your professional and personal development.
Application
If you have any questions about the position, you are welcome to contact Senior Development Manager, Mark Hougaard at e-mail: [email protected].
We hold regular interviews and end the recruitment process when the right candidate has been found.
We are looking forward to hearing from you!
Due to GDPR you can only apply via the link
All employees of XCI must be able to obtain a security clearance, which is why we will ask you to present a clean criminal record during the recruitment process.